U.S. Pat. No. 3,957,381 to Schafer discloses a coaxial, double-cone, frictional hub-to-shaft connector. The connector includes two clamping rings. The inner surface of the outer ring and the outer surface of the inner ring are conical surfaces, which engage with each other. Tightening screws to the side of the shaft tighten the connector by drawing the rings together in axial direction. As the rings are drawn together, the inner ring clamps against the shaft and the outer ring against an inner surface of the hub.
Splines are ridges or teeth on a shaft that mesh with grooves in a hub or gear wheel, for example, that is located on the shaft. Spline connections allow torque to be transferred between the shaft and the mating piece. Some spline connections are prone to backlash. An alternative to splines is a keyway and key, which, however, may not be as durable.
Cranks having a split-ring connecting portion can be tightened around a shaft. The connection may or may not have splines. The connection can be tightened using a screw located to the side of the shaft.
A tight press fit can be used to connect a solid shaft to a mating piece. This requires tight control of tolerances and typically a large force to press the two components together.
Other methods of joining a shaft to a mating piece include the use of thermal expansion and contraction. For example, a shaft is cryogenically cooled to slip-fit into an interference hole in a wheel hub. As the shaft warms, it expands and forms a strong friction joint with the hub. These joints are difficult to separate.
This background information is provided to reveal information believed by the applicant to be of possible relevance to the present invention. No admission is necessarily intended, nor should be construed, that any of the preceding information constitutes prior art against the present invention.